Leukoedema of the oral mucosa is a whitish or whitish-gray edematous lesion of the buccal and labial oral mucosa. The condition is seen most frequently among black people, and has not yet been reported in the Korean dermatologic literature. We report a 28-year-old Korean woman affected by leukoedema of the oral mucosa. She presented with a 3 year history of white plaques on both buccal mucosae. The diagnosis was clinically based on the presence of white plaques on both buccal mucosae which disappeared when the lesion was stretched, and histologically based on the acanthosis and intracellular edema.